Heat pump with intgeral solar collector

ABSTRACT

The present invention generally relates to heat pumps that utilize at least one thermal source operating with the same working fluids. In one embodiment, the present invention relates to a hybrid solar heat pump comprised of at least one microchannel heat exchanger with integral solar absorber, at least one compression (i.e., mass flow regulator) device as the heat pump for concurrent compression to a higher pressure and mass flow regulator of the working fluid, and at least one working fluid accumulator with the entire system operating with the same working fluid. The present invention also generally relates to heat pump systems that utilize an inventory management system to provide both efficient and safe operation under a wide range of operating conditions.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. Patent ApplicationSer. No. 61,231,674 filed Aug. 6, 2009, having the title “Solarcollector with expandable fluid mass management system” and U.S. PatentApplication Ser. No. 61,231,238 filed Aug. 4, 2009, having the title“Heat Pump with Integral Solar Collector” and included as reference onlywithout priority claims. Numerous additions have been made since thefiling of the provisional patent applications cited earlier. Theseinclude FIGS. 9-14, and FIG. 17. The combining of the two provisionalfilings have lead to some of the original figures being renumbered tomaintain like numerals for like components.

FIELD OF THE INVENTION

The present invention generally relates to a heat pump system having ahighly integrated mass management system and external heat source toincrease operating efficiency and reduce capital cost. In allembodiments, the present invention utilizes the same working fluidwithin all thermodynamic cycles, and the present invention utilizesgravity to discharge a relatively cooler and more dense fluid asdisplaced by a volumetrically equivalent relatively warmer and lessdense fluid.

BACKGROUND OF THE INVENTION

Due to a variety of factors including, but not limited to, globalwarming issues, fossil fuel availability and environmental impacts,crude oil price and availability issues, alternative energy sources arebecoming more popular today. One such source of alternative and/orrenewable energy is solar energy. One such way to collect solar energyis to use a solar receiver to focus and convert solar energy into adesired form (e.g., thermal energy or electrical energy). Thermal energyharvested from the sun is known in the art to be utilized in absorptionheat pumps, domestic hot water and industrial processes, powergenerating cycles through the heating of a secondary heat transferfluid, power generating cycles through the direct heating of powergenerating working fluid such as steam, and for heating. Furthermore, itis recognized that a wide range of energy consumers can be supplied viaelectrical and/or thermal energy such as air conditioning,refrigeration, heating, industrial processes, and domestic hot water.Given this, solar collectors that function in efficient manners aredesirable.

Traditional thermal activated processes effectively consider every unitof energy into the system. Furthermore by definition solar energy is afunction of solar intensity and thus at the minimum is absent during thenighttime, unless significant thermal storage is utilized that iscurrently very expensive. Additionally, it recognized in the art thatvapor compressor heat pumps have coefficients of performance “COP”substantially higher than absorption heat pumps. And hot water heatersutilizing vapor compressor driven heat pumps also have substantiallyhigher COPs as compared to direct heating of hot water having COPs lessthan unity. In addition, traditional solar collectors, particularly flatpanel collectors, are temperature constrained due in large part todeclining efficiencies as a function of temperature and the degradationof the working fluid which is often a mixture of a glycol and water.Solar collectors typically fall into the category of pump driven workingfluid circulation or thermosiphon that respectively have the deficiencyof requiring a pump or orientation of solar collector with respect tothe “condenser”.

Heat pumps also have significant limitations that limit temperatureincluding the requirement for oil lubrication that would sufferoxidative destruction at the higher temperatures desired within heatpumps. Additionally, the working fluid in virtually all refrigerants issignificantly expandable across a wide operating temperature range.

The combined limitations of each individual component being the solarcollector and the heat pump presents significant challenges that arefurther exasperated when high integration using the same working fluidfor both devices is realized.

Traditional solar systems utilize a non-expandable working fluid underpressures less than 50 psia, or working fluids having expandabilityratios between the cold and hot temperatures of less than 3. Thetraditional solar systems utilize a working fluid that is a heattransfer fluid and thus isn't directly compatible as a thermodynamiccycle working fluid. As noted, the density of the working fluid by beingexpandable changes by an order of magnitude as a function of operatingpressure and temperature. Furthermore by definition solar energy is afunction of solar intensity and thus at the minimum is absent during thenighttime, unless significant thermal storage is utilized that iscurrently very expensive, the system will experience substantial changesin density according to operating and ambient conditions.

SUMMARY OF THE INVENTION

The present invention is directed to the use of expandable fluids forthermally activated processes. The expandable fluid when heated hasdecreasing density given the same pressure, and increasing the pressurecreates heat of compression. The heat of compression is realized in theart through the operation of a heat pump. The further coupling of heatthe expandable fluid using either solar energy or other externallycombusted fuels enables a significant reduction of capital cost thuslowering the levelized cost of energy, whether that energy be in theform of thermal or electricity/mechanical energy. The change in densityfurther enables one power consuming device, which is a heat pumpoperable as a turbocompressor, turbopump, or other configurations ofgenerally recognized compressors to perform a secondary function ofregulating the inventory of working fluid within the thermodynamic cyclethat the heat pump operates within.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sequential flow diagram of one embodiment having multipleconfigurations of an integrated solar collector and heat pump inaccordance with the present invention;

FIG. 2 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump having a supplemental fluid accumulator inaccordance with the present invention;

FIG. 3 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump having multiple thermal sinks inaccordance with the present invention;

FIG. 4 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump operating as a radiant cooler inaccordance with the present invention;

FIG. 5 is a sequential flow diagram of one embodiment of an integratedsolar collector switchable as a thermal source or sink, and heat pump inaccordance with the present invention;

FIG. 6 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump with an integrated desiccant dehumidifierin accordance with the present invention;

FIG. 7 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump with an integrated power generatingexpander in accordance with the present invention;

FIG. 8 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump having multiple thermal sinks and anintegrated photovoltaic cell in accordance with the present invention;

FIG. 9 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump configured as a domestic hot water systemin accordance with the present invention;

FIG. 10 is a sequential flow diagram of one embodiment of an integratedsolar collector with external combustion to superheat working fluid andheat pump configured as a cooling system in accordance with the presentinvention;

FIG. 11 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump configured with solar collector as apreheat stage of external combustion stage in accordance with thepresent invention;

FIG. 12 is a sequential flow diagram of one embodiment of an integratedsolar collector and heat pump configured with solar collector as asuperheat stage of external combustion exhaust gases and heat pump heatof compression stages in accordance with the present invention;

FIG. 13 is a sequential flow diagram of one embodiment of an integratedpower generation cycle with a heat pump cycle powered by powergeneration cycle configured for cooling in accordance with the presentinvention;

FIG. 14 is a sequential flow diagram of one embodiment of an integratedpower generation cycle with a heat pump cycle powered by powergeneration cycle configured for cooling, and a working fluid inventorymanagement system in accordance with the present invention;

FIG. 15 is a sequential flow diagram of one embodiment of an integratedsolar collector and inventory mass management system operating with amechanically driven pressure generating device in accordance with thepresent invention;

FIG. 16 is a sequential flow diagram of one embodiment of an integratedsolar collector and inventory mass management system operating in ahybrid thermosyphon approach in accordance with the present invention;and

FIG. 17 is a sequential flow diagram of one embodiment of an integratedsolar collector and inventory mass management system operating with aseries of individually operated fluid circuit branches in accordancewith the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The term “non-linear”, as used herein, includes any surface of a solarreceiver whose surface shape is described by a set of nonlinearequations.

The term “microchannel”, as used herein, includes channel dimensions ofless than 2.5 millimeters.

The term “reflector”, as used herein, includes a surface or surfacecoating that reflects greater than 50% of at least one portion of theincoming light spectrum, which includes the portions of visible,infrared, and ultraviolet.

The term “in thermal continuity” or “thermal communication”, as usedherein, includes the direct connection between the heat source and theheat sink whether or not a thermal interface material is used.

The term “multipass”, “multi-pass”, or “multiple passes”, as usedherein, includes a fluid flow into at least one portion of a heatexchanger and out of at least one other portion of a heat exchangerwherein the at least one portion of the heat exchanger and the at leastone other portion of a heat exchanger can either be thermally isolatedfrom each other or in thermal continuity with each other.

The term “boiler”, as used herein, includes a heat exchangertransferring thermal energy into a working fluid wherein the workingfluid is comprised of at least 5% vapor phase.

The term “superheater”, as used herein, includes a heat exchangertransferring thermal energy into a working fluid wherein the heatexchanger is used to convert saturated steam into dry steam.

The term “fluid inlet” or “fluid inlet header”, as used herein, includesthe portion of a heat exchanger where the fluid flows into the heatexchanger.

The term “fluid discharge”, as used herein, includes the portion of aheat exchanger where the fluid exits the heat exchanger.

The term “expandable fluid”, as used herein, includes the all fluidsthat have a decreasing density at increasing temperature at a specificpressure of at least a 0.1% decrease in density per degree C.

The term “heat transfer fluid” is a liquid medium utilized to conveythermal energy from one location to another. The terms heat transferfluid, working fluid, and expandable fluid are used interchangeably.

The present invention generally relates to a solar collect system havingan integral working fluid management system that enables the system toincrease or decrease the mass of the working fluid within thecirculation loop of the closed loop system. The present invention alsogenerally relates to a heat pump system having an integral solarcollector that utilizes one working fluid in common between the twoelements.

Here, as well as elsewhere in the specification and claims, individualnumerical values and/or individual range limits can be combined to formnon-disclosed ranges.

The heat transfer fluid within the embodiments is preferably asupercritical fluid as a means to reduce the pressure drop within theheat exchanger. The supercritical fluid includes fluids selected fromthe group of organic refrigerants (R134, R245, pentane, butane), gases(CO2, H2O, He2), The specifically preferred supercritical fluid is voidof hydrogen as a means to virtually eliminate hydrogen reduction orhydrogen embrittlement on the heat exchanger coatings or substraterespectively. The particularly preferred supercritical fluid has adisassociation rate less than 0.5% at the operating temperature in whichthe heat exchanger operates. The specifically preferred heat transferfluid is the working fluid wherein the combined energy produced (i.e.,both thermal, and electrical) displaces the maximum amount of dollarvalue associated with the displaced energy produced within all of theintegrated components including thermodynamic cycle operable within apower generating cycle, vapor compression cycle, heat pump cycle,absorption heat pump cycle, or thermochemical heat pump cycle.

All of the embodiments can be further comprised of a control systemoperable to regulate the mass flow rate of the working fluid into thesolar receiver, with the ability to regulate the mass flow rateindependently for each pass by incorporating a fluid tank havingvariable fluid levels optionally interspersed between at least one passand the other. One method of control includes a working fluid inventorymanagement system. The control system regulates the mass flow ratethrough methods known in the art including variable speed pump, variablevolume valve, bypass valves, and fluid accumulators. The control systemis further comprised of at least one temperature sensor for fluiddischarge temperature and at least one temperature sensor for ambientair temperature or condenser discharge temperature.

Exemplary embodiments of the present invention will now be discussedwith reference to the attached Figures. Such embodiments are merelyexemplary in nature and not to be construed as limiting the scope of thepresent invention in any manner. The depiction of heat exchangerspredominantly as microchannel heat exchangers having linear porting ismerely exemplary in nature and can be substituted by complex shapedporting of microchannel dimensions or porting greater than defined bymicrochannel practice. The depiction of solar collectors predominantlyas flat panel non-tracking solar absorbers with integral microchannelheat exchangers is merely exemplary in nature and can be substituted bytracking collectors of 1 axis or 2 axis type, vacuum evacuated tubes orpanels, switchable configuration between solar absorber or solarradiator mode, low concentration fixed collector, or high concentrationtracking collectors. The depiction of heat pump as a vapor compressordevice is merely exemplary and can be substituted with an absorptionheat pump. The compressor type can include a positive displacementdevice, a gerotor, a ramjet, a screw, and a scroll. Furthermore, andimportantly, the heat pump can be a turbopump, a positive displacementpump where the selection of the device to increase the working fluidpressure and operate as a mass flow regulator is determined by thedensity at the inlet pressure and discharge outlet. When the incomingworking fluid has a density greater than 50 kg per m3, or preferablygreater than 100 kg per m3, or specifically greater greater than 300 kgper m3. The depiction of valves as standard mass flow regulators ismerely exemplary in nature and can be substituted by variable flowdevices, expansion valve, turboexpander, two way or three way valves.The depiction of methods to remove heat from the working fluid as acondenser is merely exemplary in nature as a thermal sink and can besubstituted by any device having a temperature lower than the workingfluid temperature including absorption heat pump desorber/generator,process boilers, process superheater, and domestic hot water. Thedepiction of desiccant dehumidifier as liquid desiccant dehumidifier ismerely exemplary and can be substituted by an adsorption solid desiccantdehumidifier, and high surface area hydrophilic powders. The depictionof geothermal as thermal source can be low depth subsurface, moderatedepth geothermal wells, or high depth geothermal sources such asobtained from oil wells. The depiction of expander as turbine is merelyexemplary as a method to reduce the pressure of the working fluidenables the generation of mechanical or electrical energy and can besubstituted by turboexpander, positive displacement device, a gerotor orgeroller, a ramjet, screw, or scroll device. The depiction ofphotovoltaic cell as single concentration device can be substituted bythin film, low concentration device, Fresnel lens, and highconcentration devices.

The control system is further comprised of at least one temperaturesensor for fluid discharge temperature and at least one temperaturesensor for ambient air temperature or condenser discharge temperature.

Exemplary embodiments of the present invention will now be discussedwith reference to the attached Figures. Such embodiments are merelyexemplary in nature. Furthermore, it is understand as known in the artthat sensors to measure thermophysical properties including temperatureand pressure are placed throughout the embodiments as known in the art,most notably positioned to measure at least one thermophysical parameterfor at least one thermodynamic state point. The depiction of solarcollectors predominantly as flat panel non-tracking solar absorbers withintegral microchannel heat exchangers is merely exemplary in nature andcan be substituted by tracking collectors of 1 axis or 2 axis type,vacuum evacuated tubes or panels, switchable configuration between solarabsorber or solar radiator mode, low concentration fixed collector, orhigh concentration tracking collectors. The depiction of pump as a vaporcompressor device is merely exemplary and can be substituted with apositive displacement device, a gerotor, a ramjet, a screw, and ascroll. Furthermore, and importantly, the pump can be a turbopump, apositive displacement pump where the selection of the device to increasethe working fluid pressure and operate as a mass flow regulator isdetermined by the density at the inlet pressure and discharge outletwhen the incoming working fluid has a density greater than 10-50 kg perm3, or preferably greater than 100 kg per m3, or specifically greatergreater than 300 kg per m3. The depiction of valves as standard massflow regulators is merely exemplary in nature and can be substituted byvariable flow devices, expansion valve, turboexpander, two way or threeway valves. The depiction of methods to remove heat from the workingfluid as a condenser is merely exemplary in nature as a thermal sink andcan be substituted by any device having a temperature lower than theworking fluid temperature including absorption heat pumpdesorber/generator, liquid desiccant dehumidifier, process boilers,process superheater, and domestic hot water. With regard to FIGS. 1through 17, like reference numerals refer to like parts.

The function of the mass management system is to serve as a means ofadding or removing the mass of expandable fluid from the fluidaccumulator into at least one circuit of the solar collector.Hereinafter, the term “adding fluid” is increasing the mass ofexpandable fluid into the fluid accumulator by at least 0.5% on a weightbasis. Hereinafter, the term “removing fluid” is decreasing the mass ofexpandable fluid into the fluid accumulator by 0.5% on a weight basis.It is understood that adding fluid into the fluid accumulator isremoving fluid from the at least one circuit of the solar collector,hereinafter referred to as “remove fluid from the solar collector”. Andremoving fluid from the fluid accumulator is adding fluid into the atleast one circuit of the solar collector, hereinafter referred to as“add fluid into the solar collector”.

Turning to FIG. 1, FIG. 1 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. The circles containing “A” and “B” are state pointindicators to provide continuity of working fluid flow between thevarious alternate scenarios 1 through 4. In the embodiment of FIG. 1heat pump solar collector is comprised of heat pump 10 in fluidcommunication with a solar collector 20 with a temperature sensor 32measuring the discharge temperature of the working fluid from the heatpump 10. Another temperature sensor 30 measures the dischargetemperature of the working fluid as it leaves the solar collector 20 andprior to the fluid entering the thermal sink 40 which is in fluidcommunication with the solar collector 20. Another temperature sensor 31measures the discharge temperature after leaving the thermal sink 40. Apressure sensor 50 measures the discharge pressure from the heat pump10, though the actual placement of the pressure sensor 50 can beanywhere downstream of the heat pump 10 discharge and upstream of apressure-reducing device including an expansion valve or turboexpander.One exemplary method of control is to vary the discharge pressure of theheat pump 10 such that the temperature of the working fluid beingdischarged after the solar collector, which enables the heat pump energyinput to be minimized where the heat pump 10 concurrently achieves thedesired working fluid mass flow requirement and discharge temperatureprior to the solar collector. The discharge pressure downstream of theheat pump 10 is a function of the solar flux on the solar collector 20as a method of minimizing the operating costs of the heat pump withintegral solar collector as the heat pump requires mechanical and/orelectrical energy. The heat of compression resulting from the heat pumpprovides a high coefficient of performance temperature gain (i.e., lift)that is subsequently increased further by the solar collector 20. Thecontrol system decreases the pressure gain to ensure that the thermalsink 40 both achieves the required heat transfer and dischargetemperature such that the heat pump, when the solar collector providesthe majority of the heat source into the working fluid, operatespredominantly as a mass flow regulator resulting in a reduced operatingcost of the heat pump. Another advantage of this embodiment is theelimination of a heat exchanger to transfer thermal energy captured fromthe solar collector 20 into the working fluid, and also eliminating asecondary heat transfer fluid within the solar collector 20. Thepreferred working fluid is a fluid that has virtually no (e.g., lessthan 1.0% preferred, less than 0.5% specifically preferred, and lessthan 0.05% particularly preferred) thermal degradation resultingparticularly from solar collector stagnation. One exemplary workingfluid includes carbon dioxide, with the particularly preferredembodiment having a heat pump discharge pressure greater than thesupercritical pressure of carbon dioxide. Additional working fluidsinclude refrigerants, water, and gases. The particularly preferredembodiment is the selection of carbon dioxide with a discharge pressuregreater than it's supercritical pressure and the solar collector 20being a microchannel device to achieve superior heat transfer with lowpressure drops. Another important design advantage is the selection of aheat pump 10 device that either operates oil free, thus eliminating thepotential of hydraulic oil from disassociating (i.e., breaking down)with the solar collector 20. Alternatively the heat pump can utilize anelectrostatic collector to collect any lubricant utilized within theheat pump, with one exemplary being ionic liquids. The ionic liquid hasthe further advantage of having essentially no vapor pressure incombination of having electrostatic attraction as a method of limitingthe heat pump 10 lubricant from entering the solar collector 20. FIG. 1shows four alternative configurations such that “A” is the inlet of theworking fluid into the heat pump 10, and “B” is the discharge of theworking fluid downstream of the thermal sink 40. The first alternate“alternate 1” depicts an expander 60 downstream of the thermal sink 40as a method of recovering at least a portion of themechanical/electrical energy expended during in order to obtain the heatpump compression. This alternate configuration would be typical fordomestic hot water, air conditioning, refrigeration, industrialprocesses including processes currently serviced by traditionalcombustion powered boilers, furnaces, dryers, etc. The expander's 60discharge pressure is regulated by using feedback on the measuredpressure by pressure sensor 50 and discharge temperature as measured bytemperature sensor 33. It is further anticipated that an externalcombustor can be downstream of the solar collector 20 and upstream ofthe thermal sink 40 as a method to further increase the working fluidtemperature. This configuration is especially desired for industrial orpower generation processes that involve heating of air (i.e., less densethan working fluid thus requiring significantly larger heat exchangers)as a method of superheating the working fluid to the desired operatingtemperature of the thermal sink 40. The invention utilizing the sameworking fluid for the heat pump as the solar collector for temperaturesexceeding 350C can only be done using a small set of working fluids mostnotably ammonia and particularly preferred carbon dioxide “CO2”. Wateris another alternative fluid, though less desirable due to thediscontinuous thermophysical properties as the water transitions tosteam. The second alternate configuration replaces the expander with anexpansion valve 90 where the expansion valve as known in the art canoperate as a variable controlled device, open/close switch, andmodulated to be a pulsing device to enhance heat transfer properties.The expansion valve, which is a special type of fluid control valve 90enabling pressure reduction discharge pressure is regulated by usingfeedback on the measured pressure by pressure sensor 52 and dischargetemperature as measured by temperature sensor 34. This configuration,though not as efficient as alternate 1, has a lower capital cost thusbeing implemented when the system scale or financial return oninvestment doesn't justify the additional expense of an energy recoveryexpander 60. The working fluid downstream of the expansion valveprovides cooling through an evaporator 80 thus operating as an airconditioner, chiller, refrigerator, or freezer which is dependent on thedischarge temperature as measured by temperature sensor 34. Alternateconfiguration 3 simply depicts a closed loop system such that the heatpump effectively operates as a mass flow regulator, whereby the pressuregain between the heat pump 10 inlet is a nominal amount solely toovercome pressure losses associated with the working fluid passingthrough the entire circulation loop including the solar collector 20.Alternate configuration 4 is further comprised of a fluid accumulator130 and a control valve 95 as a method to buffer the inventory ofworking fluid within the circulation loop. The fluid accumulator in itssimplest form operates as a temporary storage of working fluid when theoperating pressure within the circulation loop is within 10 psi of themaximum operating pressure of any individual component. The inventionincorporates a control system to open and close valving of the alternate4 configuration, which is preferably configured as a parallel circuitwith any of the prior alternate configurations. The preferred embodimenthas an operating pressure at state point A of less than thesupercritical pressure of the working fluid, which for CO2 is less than1000 psi. The particularly preferred embodiment has a working fluidpressure of less than 800 psi. Another embodiment is the heat pump cycleoperating as a fully subcritical cycle in which state point A has anoperating pressure of less than 400 psi. The operating pressure at statepoint B is preferred to be supercritical, which for CO2 is above 1200psi as to ensure low pressure drop throughout the solar collector 20.The pressure differential across the heat pump 10 is varied such thatthe working fluid has a compressibility greater than 10%, which isdependent on realizing a heat of compression greater than 10 degreesFahrenheit. The particularly preferred heat of compression is thegreater of 20 degrees Fahrenheit, or such that the temperaturedownstream of heat pump 10 is at least 15 degrees Fahrenheit higher thanthe ambient air temperature. The preferred method of control is tooperate the low-side pressure of the heat pump when under Alternate 2such that the expansion yields a cooling temperature of at least 2degrees Fahrenheit cooler than the air conditioning or refrigeration setpoint. Under Alternate 2 it is further desirable to maximize thecombined thermal heating by first stage of heat of compression followedby the solar collector, whereby the solar collector heating varies inreal-time as a function of the thermal sink mass flow rate (i.e.,heating domestic hot water, industrial process heating, etc.) and solarirradiance flux. The low-side circuit pressure (i.e., upstream of heatpump 10) and pressure ratio under Alternate 1 is selected such that themechanical work realized by the expander 60 closely matches the workinput requirement of the heat pump 10 to minimize electricityrequirements.

Turning to FIG. 2, FIG. 2 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 2 heat pump solar collectorthe heat pump 10 upstream of the solar collector 20 is further comprisedof a fluid accumulator 130 configured predominantly as an emergencyworking fluid inventory storage vehicle where an open/close fluid valve90 enables a partial stream of the working fluid, which is now at thehigher pressure as measured by pressure sensor 50 having a temperatureas measured by temperature sensor 31. The working fluid passes through acondenser 70 in order to increase the density of the working fluid priorto entering the fluid accumulator 130. The preferred configuration ofthe condenser 70 is within the fluid accumulator 130, thus enabling thecondenser (effectively a heat exchanger) to operate as anevaporator/heater. The control system would switch the condenser fromcooling to heating mode once the heat pump discharge pressure (i.e.working fluid pressure downstream of the heat pump discharge) becomes atlower than the maximum operating pressure minus an anti-cyclingthreshold. The control system would then subsequently open the valve 90once the working fluid within the fluid accumulator 130 exceeds thetarget set point as measured by temperature sensor 30.

Turning to FIG. 3, FIG. 3 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 3 heat pump solar collectordepicts one scenario having parallel circuits and multiple thermalsinks. The heat pump 10, as noted earlier can operate as mass flowregulator (i.e., booster pump), more traditional vapor compressor, ormore traditional turbopump. A control system operates the valves as amethod of controlling the mass flow within each parallel circuit. Thetop circuit is controlled by valve 90 to enable the working fluid topass through the solar collector 20. The invention anticipates the solarcollector 20 operating either as a solar absorber or solar radiator thusproviding the ability to provide “free” heating or cooling respectivelyby leveraging the high surface area. The working fluid downstream of thesolar collector 20 transfers thermal energy via a heat exchanger 80,which can be manufactured using a wide range of materials (e.g.,conductive polymers, aluminum, stainless steel, etc.) and designed usingmethods known in the art (e.g., microchannel, shell and tube, plate,etc.), into a thermal sink #2 41. The working fluid downstream of theheat exchanger 80 mixes with working fluid that passes through valve 91,thus effectively operating as a solar collector bypass valve, andsequentially passes through a second thermal sink 40 that has a lowertarget set point than thermal sink 41. Another thermal sink #3 42 asdepicted removes more thermal energy from the working fluid, though theworking fluid temperature will be at a lower temperature than the twoaforementioned thermal sinks 41 and 40. The last depicted valve 92enables working fluid to enter the fluid accumulator 130. The fullworking features as noted in FIG. 2 are not repeated visually for thepurpose of brevity. A key feature of the heat pump system is the abilityto adapt to changing solar conditions, ambient weather conditions (e.g.,such as changing temperatures and humidity levels), and changing thermalload requirements (e.g., both heating and cooling). Fluid valves 90, 91,and 92 are optimally variable flow valves enabling the full mass flowrate achieved by the heat pump 10 to be segmented to meet the individualheat transfer requirements of thermal sink 40, 41, and 42. As each fluidvalve is modulated the working fluid inventory within the thermodynamiccycle varies, and thus the inventory management within the fluidaccumulator 130 must modulate fluid valves 92 and 93 to enable fluid tobe added and removed from the thermodynamic cycle high-side and low-sidecircuits.

Turning to FIG. 4, FIG. 4 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 4 heat pump solar collectoroperates as a radiant cooler. A heat pump 10 increases the operatingpressure as measured by the pressure sensor 50 of the working fluidwhich also has its temperature increased due to heat of compression asmeasured by temperature sensor 30. A secondary heat transfer fluid, suchas domestic hot water is circulated by a pump 160 through a heatexchanger 80 to remove thermal energy of the working fluid through athermal sink 40. This serves the purpose of providing the first stage ofcooling prior to reaching the solar collector 20 configured in theradiant cooling (i.e., thermal emitting as opposed to solar absorbing)mode. The inlet temperature into the solar collector 20 is measured bytemperature sensor 31 and the discharge temperature is measured bytemperature sensor 32. The solar collector 20 when operating as aradiant cooler dissipates black body radiation to the sky and thereforeeffectively operates as a precooler/subcooler to the working fluid priorto reaching the expansion valve 91. The now expanded working fluidprovides cooling that absorbs thermal energy from a thermal source inthermal communication with the evaporator 80. The heat pump 10 inletpressure and temperature are measured respectively by pressure sensor 51and temperature sensor 33. An alternate configuration for the thermalsink 40 is depicted in alternate 1 as an air condenser utilizingcondenser fans 100 instead of a secondary heat transfer fluid.

Turning to FIG. 5, FIG. 5 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 5 heat pump solar collectordepicts another configuration for switching the solar collector 20between a thermal sink 40 and thermal source mode. In this configurationthe solar collector, which is optionally under vacuum while operating inthermal source mode, the solar collector has ambient air flowing overthe solar collector 20 surface area. The working fluid then subsequentlypasses through the thermal sink 40. Two two-way valves 111 and 110 aredepicted here to switch fluid flow direction such that the heat pump canoperate in air conditioning or heating mode, known in the art as areversible heat pump. The heat pump 10 has the common evaporator 80 andexpansion valve 91 (alternatively expander) and condenser (which isdepicted as either the thermal sink 40 or solar collector 20).Configuration 1 depicts the solar collector 20 operating as a radiantcooler. Under such a radiant cooler mode, the heat pump 10 consumeselectricity as provided by either the electrical grid or off-gridrenewable energy. The heat pump operating parameters such as high-sidepressure and low-side pressure are varied to meet the specificrequirements of thermal sink #1 40 and cooling levels required asrealized by evaporator 80. Again, alternate 1 enables the use ofcondenser fans 100 to accelerate the removal of heat from the workingfluid, where the thermal sink #1 40 is operable as an air sidecondenser.

Turning to FIG. 6, FIG. 6 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 6 heat pump 10 solarcollector 20 is depicted further comprising a liquid desiccant generator120 and geothermal 140 as a thermal sink. It is understood that the heatpump with integral solar collector can operate with either the liquiddesiccant generator 120 or the geothermal 140 heat sink, as well as theshown combination. The heat pump 10 increases the operating pressure ofthe working fluid in part by utilizing a controllable two way valve 111to provide back pressure upstream of the solar collector 20, while alsoserving as a mass flow control (i.e., working fluid pump). The solarcollector 20 increases the working fluid temperature of the portion ofthe working fluid being transported through the collector as determinedby the control system and regulated by the amount of fluid bypass againwith the two way valve position 111. The operation in FIG. 6 depicts theheat pump 10 operating as an air conditioning or refrigeration device toprovide the sensible cooling while the liquid desiccant generator 120provides the latent cooling. The goal is thus to provide coolingtherefore a significant portion of the working fluid is desired tobypass, whereby regulating fluid diode 700 prevents backflow into theheat exchanger 80. The solar collector 20 boosts the working fluidtemperature through a heat exchanger 80 as required to regenerate theliquid desiccant solution. The working fluid having been transportedthrough the parallel circuit is combined upstream of the condenser 70where the working fluid temperature approaches the ambient temperature.It is understood that the condenser 70 can be selected from the range ofknown condensers including wet, air, evaporative, etc. FIG. 6 alsodepicts a working fluid mass management control system thoughrepresented for brevity by a control fluid valve 93 to enable workingfluid to enter or leave the fluid accumulator 130 as noted in theearlier embodiments. The working fluid can then be optionally subcooledthrough a heat exchanger 80 in thermal communication with a shallowdepth (i.e. surface as known in the geothermal heat pump application, ascompared to deep well geothermal for power generation) geothermal 140that serves as a thermal sink upstream of the expansion valve 92. Thefluid control valve 92 operates as an expansion valve to decrease theoperating pressure while enabling rapid cooling of the working fluidthat subsequently absorbs heat through the evaporator 80.

Turning to FIG. 7, FIG. 7 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 7 heat pump solar collectordepicts an integral power generating cycle with an airconditioning/refrigeration thermodynamic cycle where both systemsoperate on the same working fluid. Beginning the cycle downstream of theheat pump 10, the heat pump 10 increases the working fluid pressure tothe same low side pressure of the power generating cycle (which isdownstream of the valve 91, fluid diode 700 to prevent backflow andcondenser 70). The working fluid downstream of the heat pump 10 thenpasses through the condenser 71 to condense the working fluid prior toreaching the pump 160 as a method of limiting cavitation. The pump 160subsequently raises the working fluid, which is now at a significantlyhigher density, to the power generating high side pressure. The highpressure working fluid, which has increased the working fluidtemperature by the heat of compression, now passes through the solarcollector 20 to vaporize and optionally to superheat the fluid as ameans of increasing the enthalpy and thermodynamic efficiency of thepower generating cycle. The now superheated working fluid enters theexpander (e.g., turbine) 150 inlet in order to produce shaft work (i.e.,mechanical energy) that can further be transformed into electricity orhydraulic energy. As known in the art, the working fluid enters thecondenser 70 in order to reduce the pumping energy requirements toreturn the relatively cool working fluid to the high side pressure. Itis understood that the turbine can be any expander device, as the pumpcan also include a turbopump or positive displacement devices. Thecontrol system regulates in real time the mass flow of the working fluidthat will further be expanded in order to match the airconditioning/refrigeration demands with thermal energy being transferredthrough the evaporator 80. It is further understood that the pump 160,heat pump 10, and expander 150 can operate at partial loads throughmeans as known in the art. The heat pump 10 can optionally have anelectric motor 1000 with a decoupling mechanism such as a decoupler 1010to engage or disengage the electric motor. Though depicted only in FIG.7, it is understood that the electric motor/generator 1000 and decoupler1010 can be implemented in all scenarios for heat pump operation.

Turning to FIG. 8, FIG. 8 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector in accordance with thepresent invention. In the embodiment of FIG. 8 heat pump solar collectordepicts a hybrid solar thermal and photovoltaic configuration. Theprecise objective of the integrated heat pump and photovoltaic cellsystem is to operate with the control system pressure and temperaturecontrol such that the working fluid transforms from aliquid/supercritical to a vapor/superheated fluid within the backside ofthe photovoltaic cell 200. The operating pressure is dynamicallymodulated such that the temperature at state point #2 is less thanlesser of the maximum junction temperature of PV cell 200 or desiredoperating temperature. The working fluid subsequently passes through asolar collector 20 to ensure that the working fluid doesn't createcavitation in the heat pump 10. The now high pressure working fluid alsoat the elevated temperature due to heat of compression is atsufficiently high temperatures to drive a range of thermal sinks. Thesethermal sinks include thermally activated chillers, such as single,double or triple effect absorption chillers, and adsorption chillers230. Subsequently the working fluid passes through thermal sinksrequiring sequentially lower operating temperatures such as process heat240 and then domestic hot water 250. The control system will enable theworking fluid to pass through the condenser 70 in the event the workingfluid temperature remains higher than the ambient or wet bulbtemperature, which would be obtained by activating the condenserfans/motors. The working fluid now transfers thermal energy by absorbingenergy through the evaporator 80 and now returning to the backside ofthe PV cell 200 where thermal energy is transferred into the workingfluid through the embedded microchannel heat exchanger 210.

Turning to FIG. 9, FIG. 9 is a sequential flow diagram of one embodimentof a heat pump with integral solar collector and/or combustor inaccordance with the present invention. In the embodiment of FIG. 9 heatpump solar collector depicts a hot water or steam heat pump utilizingthe same working fluid within the entire system.

The specific implementation is a more efficient alternative totraditional boilers, as the coefficient of performance “COP” is greaterthan 1.0. The particularly preferred COP is greater than 1.20, and thespecifically preferred COP is greater than 1.60. The method of controlincludes a dynamic control system that ensures the operating temperatureof the working fluid downstream of the solar collector 20, which ispreferably a microchannel heat exchanger, is less than the maximumworking fluid temperature and also to ensure that the working fluid is avapor prior to entering the heat pump 10. The optimal control system hasthe means to control the discharge pressure, the mass flow rate, andbypass valves including a variable fluid valve 91 to preferably avariable position that modulates the transferring of heat from theworking fluid into the hot water/steam system supply B. Flow points Aand B are utilized to respectively indicate water/steam flow moreclearly where A is relatively cold temperatures as compared to B.Beginning at the cold water source, two circulating pumps 161 and 162regulate the mass flow rate into the two respective thermodynamic cycleswith second thermodynamic cycle (i.e., power generation) and firstthermodynamic cycle (i.e., heat pump). Optimally, the thermodynamiccycle has a high-side and a low-side pressure with a high-side pressurehaving an operating pressure of at least 50 psi greater than a low-sidepressure. The one mass flow regulator (i.e., heat pump 10) is operablefor both increase the working fluid pressure from the low-side pressureto the high-side pressure and for removing or adding working fluid fromthe thermodynamic cycle into the fluid accumulator. The cold waterdischarged by circulating pump 161 enters the heat exchanger 802, whichis downstream of the expander 150, thus concurrently operates as acondenser in the power generation cycle. The power generation cycle canoperate as either a Brayton or Rankine cycle. At ambient temperatureslower than 65 degrees Fahrenheit, the optimal cycle is a Rankine cyclewith a pressure ratio across the expander 150 of greater than 2.2, andpreferably greater than 2.7. Under ambient conditions greater than 90degrees Fahrenheit, a Brayton cycle is preferred. Continuing the workingfluid enters into heat exchanger 803, which is essentially a hybridregenerator between the second and first thermodynamic cycles. Heat istransferred from the second thermodynamic cycle for the purpose ofreducing the compressibility of the working fluid, and thus minimizingcompression energy (i.e., maximize power generation); while concurrentlypreheating the working fluid prior to the heat pump 10, serving as bothpreheat and eliminating the potential for cavitation or liquid-lock. Thenow relatively warmer working fluid, which is compressible, is increasedto the high-side circuit pressure of the second thermodynamic cycle bythe circulating pump 160 (i.e., turbopump, turbocompressor, etc.)whereby the working fluid is heated externally by either or both solarcollector 20 and supplemental combustor 300 of fuel. The now superheatedworking fluid enters the expander 150 to produce mechanical shaft power,which is used to provide required energy to the heat pump 10. Thedischarge from the expander remains hot, on the order of100 degreesCelsius below the discharge temperature from heat exchanger 801, whichthis now excess heat is transferred to heat the cold water/steam. Theother path for creating hot water/steam is circulated by circulatingpump 162 into the heat exchanger 805, which obtains its thermal energyfrom the heat pump 10 heat of compression followed by waste heatrecovery of combustor exhaust 301. The working fluid exiting heatexchanger 805 is flow regulated by fluid valve 91 operable as anexpansion valve.

Turning to FIG. 10, which is the reconfiguration of FIG. 9 for producingchilled water or air conditoning instead of hot water/steam, the thermalsources of solar collector 20 and combustor 300 are transferred into theworking fluid of the second thermodynamic cycle to maximize powerproduction to drive the expander 150 via heat exchanger 801. Thefundamental difference is that the combustor exhaust 301 is now used topreheat the working fluid entering the heat pump 10 to maximize thethermal lift via heat exchanger 802, with the available thermal energybeing dissipated from the working fluid of the first thermodynamic cyclethrough condenser 70 (which can effectively be any heat exchangerproviding heat to a wide range of devices such as absorption chillers,or industrial process heat). The now “cooled” working fluid is preparedto go through an expansion valve to provide cooling.

Turning to FIG. 11, which is another reconfiguration of FIG. 9, forutilizing harvested solar thermal energy via the solar collector 20. Thepreheated working fluid is further heated by combusting fuel in thecombustor 300. The now superheated working fluid enters the expander 150to maximize power production.

Turning to FIG. 12, which is yet another reconfiguration of FIG. 9,depicts the combustor exhaust gas 301 serving as a second stage ofheating following the heat pump 10 heat of compression. The heatexchanger 801 recovers the waste heat from exhaust gas, whichparticularly under oxyfuel combustion has reduced volume for enhancedheat transfer with a smaller heat exchanger, and the configuration ofthe heat exchanger 801 as known in the art to withstand corrosivesresulting from condensable gas byproducts (NOx, SOx, etc.). The workingfluid is finally superheated by the solar collector 20 prior to beingdischarged.

Turning to FIG. 13, which is yet another reconfiguration of FIG. 9, butfor produced chilled water, air conditioning or refrigeration. Thefundamental advantage of this configuration as compared to provisionalfiling and prior art is the absence of a regenerator, thus all heattransfer out of the second thermodynamic cycle is at the low-sidecircuit pressure. Beginning the second thermodynamic cycle at thedischarge of the circulating pump 160 (i.e., turbopump, turbocompressor,etc.), the working fluid then is heated either directly by flowingthrough microchannel solar collectors (i.e., having integralmicrochannel heat exchanger 801) or indirectly from combustor 300through the heat exchanger 801. The now superheated working fluid entersthe expander 150 to produce mechanical energy to drive directly the heatpump 10. The now low-pressure working fluid has thermal energy transfervia heat exchanger 804 to any of a wide range of thermally activatedchillers 230 (e.g., double effect, single effect absorption, adsorption,etc.). Subsequent thermal energy is transferred to a desiccant generator900 via a heat exchanger 802, whereby the desiccant generator handlesthe latent load. Any remaining waste heat from the second thermodynamicpower generating cycle is removed by the condenser 70 in order tominimize circulating pump 160 energy requirements. The firstthermodynamic cycle is optimized for cooling by removing heat ofcompression through heat exchanger 805 (i.e., operable as a condenser),then pre-cooling through heat exchanger 806 using ground sourcegeothermal 910, and then using evaporative cooling 920 via heatexchanger 807. The now pre-cooled and sub-cooled working fluid isexpander through fluid valve 91 to provide cooling through heatexchanger 803 (i.e., operable as an evaporator). Alternate 1 simplychanges the order of the ground source geothermal 910 and theevaporative cooler 920. It is understood that this configuration doesnot require both geothermal and evaporative precooling.

Turning to FIG. 14, a reconfiguration of FIG. 13, integrates additionalflexibility and adaptability to changing conditions. Beginning with theheat pump 10 heat of compression and preventing any backflow via fluiddiode 700, the working fluid is directed through the two way valve 110downstream of the heat pump 10. The two way valve 110, under conditionssuitable for radiant cooling directs working fluid into solar collector20 with another downstream fluid diode 700 again to prevent backflow.Alternatively under conditions suitable for solar energy harvesting theworking fluid is diverted to the solar collector 20. When sufficientthermal energy is available from the solar flux the working fluid isdirected to the expander 150 to produce power and again using a fluiddiode 700 to prevent backflow. When conditions do not meet radiantcooling or solar harvesting, the heat pump 10 operates as a traditionalCO2 based heat pump providing heat of compression. The now relativelywarm working fluid can be utilized for a series of thermal loadsincluding thermal activated chiller 230, desiccant generator 900 anddomestic hot water 250, all via respectively heat exchangers 805, 804,and 803. Any remaining waste heat is removed via the condenser 70. Inthe event that cooling is required, the working fluid is directed toheat exchanger 802 in which evaporative cooling 920 removes additionalthermal energy and now returns back to the heat pump 10 inlet assurrounded by a series of fluid diodes 700 preventing backflow. Theworking fluid mass management system is depicted, where the fluidaccumulator 130 obtains working fluid from the high-side circuitpressure and is removed from the accumulator into the low-pressurecircuit side upstream of the heat pump 10. Alternate 1 simply depictsthe heat pump and expander on the same shaft, such to enable both theheat pump 10 and expander 150 to be in one hermetically sealed chamber,thus having an important secondary benefit of increasing the operatingpressure of any working fluid leaking from the power generating expander150. The two overlapping thermodynamic cycles (i.e., power generatingthermodynamic loop and a heat pump thermodynamic loop) has the workingfluid leaking from the power generating expander increased to a pressureof at least 5 psi greater than the low-side pressure of the powergenerating thermodynamic loop.

Turning to FIG. 15, Removing Fluid from Accumulator (Adding Fluid intoSolar Collector): There are two methods to remove working fluid from thefluid accumulator 130 with the first being the use of the solarcollector 20 to heat a portion of the working fluid remaining in themain closed loop system by absorbing solar flux and transferring thisthermal energy via an embedded heat exchanger within the solar collector20, and the second being the use of the condenser 70 as a heat source(as compared to the traditional role as a heat sink). Utilizing thefirst method, the heat pump 10 prevents backflow during normaloperation, and the control system activates the hot inlet valve 93 tothe open position when the solar collector 20 has heated the workingfluid to a target set point temperature (i.e., achieved a specifieddensity by way of the operating pressure and working fluid temperature).The discharge fluid valve 93 is subsequently opened by the controlsystem to enable the relatively low density and higher temperatureworking fluid to displace the relatively more dense and lowertemperature working fluid. The method of control includes the ability tomonitor heat pump 10 energy consumption by methods known in the artincluding mass flow meter, kilowatt-hour meter, pump performance mapswith a known inlet and discharge pressure, working fluid inlettemperature, and working fluid discharge temperature. The control systemcan also utilize a database of NIST thermophysical properties toprecisely calculate the amount of working fluid within the fluidaccumulator 130, or within the closed loop system.

Adding Fluid: The best method of adding fluid, (i.e., discharging fluidfrom the fluid accumulator into the at least one circuit of the solarcollector) centers around the condenser 70 in thermal communication withheat exchanger 802 operating in reverse mode as the removing fluid mode,thus as a thermal source instead of a thermal sink. Under this method,the control system will begin the process of using a relatively highertemperature and lower density heat transfer fluid into the embedded heatexchanger of the fluid accumulator 130 at which point of reaching eitheror both the target set point temperature and/or target set pointpressure the cold fluid valve 90 is opened (this assumes that theresulting pressure within the fluid accumulator is at least temporarilyhigher than the closed loop system pressure).

Turning to FIG. 16, FIG. 16 is a sequential flow diagram of oneembodiment of a solar collector with integral mass management system inaccordance with the present invention. In the embodiment of FIG. 16 thefluid accumulator discharges directly into the solar collectorpreferably operating as a thermosiphon. Beginning with the working fluidat state point A, at least a portion of the working fluid passes throughthe hot inlet valve 93 when the fluid accumulator is removing workingfluid from the main closed loop of the solar collector thermosiphonsystem. As with any thermosiphon system it is critical that the fluidaccumulator 130 be located above the solar collector. The expandableworking fluid having entered the fluid accumulator 130 is cooled throughthe heat exchanger 802, which is preferably contained within the fluidaccumulator. The heat transfer fluid utilized to cool the working fluidis through the accumulator condenser 70. The then subsequently cooledworking fluid within the fluid accumulator 130 is discharged through thedischarge valve 93 back into the solar collector 20, when desired andcontrolled by a control system to regulate the combination of mass flowrate of the working fluid and the operating pressure of the workingfluid within the safe margins of operation. It is understood thattemperature sensors can be placed at each state point, including withinthe fluid accumulator to enable the control system to regulate the flowof working fluid, and heat transfer fluid to remove thermal energy fromthe working fluid as a means of heating up a thermal sink includingdomestic hot water, industrial processes, heating, and even powergeneration. The depiction within FIG. 16, notably the right half of thedrawing shows the utilization of a heat transfer fluid that ultimatelyis heated by the solar collector 20 (on the bottom right side, which iseffectively the same as solar collector 20 (graphically and physicallyabove it) but showing the relative height of each component to eachother) whereby the working fluid removed from the main closed looptransfers a portion of its thermal energy to increase the density of thestored fluid and is conserved by subsequent transfer of the thermalenergy to increase from state point T1 33.1 as it passes through valve90 and the fluid accumulator condenser 70 via heat exchanger 803, nowbecoming state point D having a temperature sensor T2 33.2. This stageeffectively operates as a preheat of the heat transfer fluid, thenpasses through the condenser 70 of the main loop now becoming statepoint E having a temperature sensor T3 33.3 to continue the flow throughthe solar collector 20. The operation of the solar collector as athermosiphon requires T1<T2<T3.

It is anticipated that the removal of working fluid from the closed loopsystem into the fluid accumulator 130 can result from the solarcollector operating in essentially a stagnation mode (thus being asafety precaution to limit the solar collector from exceeding it'smaximum operating pressure specifications), the closing and/orevacuation of a parallel circuit within the closed loop system,capturing at least a portion of the working fluid “charge” within theclosed loop system prior to maintenance of the entire system, enablingthe solar collector to operate at relatively higher ambienttemperatures, and/or enabling the solar collector to operate atrelatively lower operating pressure. The counterpart is the addition ofworking fluid into the closed loop system from the fluid accumulator 130as a result of relatively lower ambient temperatures, the opening and/orfilling of a parallel circuit within the closed loop system, enablingthe solar collector to operate at relatively lower ambient temperatures,and/or enabling the solar collector to operate at relatively higheroperating pressure.

Turning to FIG. 17, the inventory management system with the centralelement of fluid accumulator 130 is in thermal communication with thecondenser 70 via the heat exchanger 802. Fluid is discharged from thefluid accumulator 130 via the discharge fluid valve 93 into thelow-pressure circuit side of the heat pump 10. Fluid enters the fluidaccumulator 130 either directly through the cold fluid valve 90 or thehot fluid valve 93 respectively when inventory is desired to beincreased and inventory is desired to be decreased in the fluidaccumulator 130. In all cases fluid entering the fluid accumulator 130is from the high-pressure circuit side of the heat pump 10. Whendesiring relatively hot working fluid, the working fluid is heatedeither by the solar collector 20 or the combustor 300. The heat pumpsystem must adapt quickly when high-side pressure circuits 901 areopened or closed, as well as low-side pressure circuits 902.

It is understood in this invention that a combination of scenarios canbe assembled through the use of fluid valves and/or switches such thatany of the alternate configurations can be in parallel enabling thesolar collector to support a wide range of thermal sinks.

The power generating expander 150 is designed to provide all of thegenerated power in the form of mechanical shaft power and furtherdesigned for the mechanical shaft power to power the mass flowregulator. The use of the fluid valves 90 serve as a back pressureregulator for the heat pump thermodynamic loop enabling to vary thehigh-side pressure of the heat pump thermodynamic loop to consume all ofthe mechanical shaft power generated by the power generating expander.

FIG. 7 depicts the use of an electric motor to generate mechanical shaftpower to operate the one mass flow regulator (i.e., heat pump 10) wheninsufficient power is available from the power generating expander 150.The electric motor has a method of decoupling (i.e., magnetic, physical,or electrical decoupler) designed to either electrically or magneticallydecouple the electric motor or mechanically disconnect the electricmotor from both the heat pump 10 and the power generating expander 150.

The fluid accumulator when operating in the thermosiphon configurationis designed to be void of a second mass flow regulator consuming greaterthan 20 watts of mechanical or electrical power. This is particularlyrealized when the working fluid is at a pressure where a decrease indensity per 10 degrees Fahrenheit increase is at least one percent. Theconfiguration of the fluid accumulator 130 is such that at least onefluid inlet port is at least one inch higher than the at least one fluiddischarge port. The method of adding working fluid is designed to havevolumetric displacement of working fluid in the fluid accumulator withworking fluid from the high-pressure circuit side having a density of atleast one percent lower than the working fluid within the fluidaccumulator 130. Another method of adding working fluid with anincreased rate of fluid addition by at least 5 percent is by preheatingthe temperature of the high-pressure circuit side at least 10 degreesFahrenheit greater than the working fluid temperature within the fluidaccumulator. Yet another method of adding working fluid is by usingsolar collectors 20 downstream of the heat pump 10 to increase theworking fluid temperature by at least 5 degrees Fahrenheit, or toincrease the rate of fluid addition by at least 5 percent throughcooling the working fluid temperature within the fluid accumulator by atleast 5 degrees Fahrenheit. While removing working fluid is best done bydecreasing the working fluid temperature by at least 5 degreesFahrenheit, or by using volumetric displacement of the working fluid inthe fluid accumulator with working fluid from the high-pressure circuitside having a density of at least one percent greater than the workingfluid within the fluid accumulator.

Optimal conditions of the overlapping thermodynamic cycle has thehigh-side pressure circuit of the second thermodynamic cycle at least 5psi greater than the low-side pressure circuit of the firstthermodynamic cycle.

Another optimal condition is achieved when the power generating systemhas solid state conversion devices including photovoltaic,thermophotovoltaic, thermoelectric, or thermionic cell. The high-sidepressure is modified to not exceed a maximum junction temperature usinga backpressure regulator. The operating pressure is selected to maintaina phase change working fluid temperature within 5 degrees Fahrenheit ofthe lesser of solid state conversion device maximum junction temperatureor design temperature.

The combined power generating and heat pump consuming efficiency isrealized when the second thermodynamic cycle is void of any heatexchangers having thermal communication between a high-pressure circuitside of second thermodynamic cycle and low-pressure circuit side ofsecond thermodynamic cycle.

The particularly preferred working fluid is carbon dioxide, with thehigh-side circuit pressure of the second thermodynamic cycle greaterthan 2000 psi, and the high-side circuit pressure of the firstthermodynamic cycle is greater than 800 psi. Another embodiment is withthe high-side circuit pressure of the second thermodynamic cycle greaterthan 2700 psi, the high-side circuit pressure of the first thermodynamiccycle is greater than 1200 psi, the high-side circuit pressure of thesecond thermodynamic cycle is greater than 2.2 times the low-sidecircuit pressure of the second thermodynamic cycle, and the high-sidecircuit pressure of the first thermodynamic cycle at least 5 psi greaterthan the low-side circuit pressure of the second thermodynamic cycle.

Yet another embodiment is where a heat exchanger is used to transferthermal energy from the second thermodynamic cycle low-pressure circuitside to the regenerator of the dehumidification (i.e., desiccantgenerator) to provide latent cooling, and a heat exchanger from thefirst thermodynamic cycle high-pressure circuit side operable as acondenser and wherein the first thermodynamic cycle is operable in acooling mode and the second thermodynamic cycle is operable as amechanically interconnected power source to the at least one mass flowregulator.

Although the invention has been described in detail with particularreference to certain embodiments detailed herein, other embodiments canachieve the same results. Variations and modifications of the presentinvention will be obvious to those skilled in the art and the presentinvention is intended to cover in the appended claims all suchmodifications and equivalents.

1. A heat pump system comprising one working fluid in at least one thermodynamic cycle and one mass flow regulator circulating a working fluid selected from at least one heat transfer fluid of water, carbon dioxide, and ammonia; both a high-side pressure circuit downstream of the one mass flow regulator and a low-side pressure circuit upstream of the one mass flow regulator; and wherein the one mass flow regulator consumes mechanical or electrical power of greater than 20 watts.
 2. The heat pump system of claim 1 further comprised of a microchannel solar collector having a microchannel diameter of less than 2.5 millimeters.
 3. The heat pump system of claim 1 wherein the at least one mass flow regulator increases microchannel solar collector working fluid.
 4. The heat pump system of claim 1 further comprised of at least two heat exchangers, wherein the at least one mass flow regulator is operable in a) power generation, b) heating, or c) cooling mode.
 5. The heat pump system of claim 2 wherein the microchannel solar collector has at least two individually controlled circuits.
 6. The heat pump system of claim 2 further comprised of a fluid accumulator tank and wherein the fluid accumulator tank is between the at least two individually controlled circuits.
 7. The heat pump system of claim 2 wherein the microchannel solar collector is operable in either solar absorbing or thermal emitting mode.
 8. The heat pump system of claim 1 further comprised of a power generating expander, a fluid accumulator, a thermodynamic cycle having a high-side and a low-side pressure with a high-side pressure having an operating pressure of at least 50 psi greater than a low-side pressure, wherein the one mass flow regulator is operable for both increasing the working fluid pressure from the low-side pressure to the high-side pressure and for removing or adding working fluid from the thermodynamic cycle into the fluid accumulator.
 9. The heat pump system of claim 1 further comprised of at least one heat exchanger for independent control of sensible cooling and at least one heat exchanger for independent control of latent cooling.
 10. The heat pump system of claim 9 wherein the at least one heat exchanger for independent control of sensible cooling and at least one heat exchanger for independent control of latent cooling designed to remove thermal energy from the thermodynamic cycle and to displace any heat exchangers between the low-side pressure and high-side pressure.
 11. The heat pump system of claim 8 wherein the power generating expander and the one mass flow regulator are both contained within a hermetically sealed chamber.
 12. The heat pump system of claim 11 wherein the one mass flow regulator is designed to increase the operating pressure of any working fluid leaking from the power generating expander.
 13. The heat pump system of claim 12 having two overlapping thermodynamic cycles comprised of a power generating thermodynamic loop and a heat pump thermodynamic loop, wherein the any working fluid leaking from the power generating expander is increased to a pressure at least 5 psi greater than the low-side pressure of the power generating thermodynamic loop.
 14. The heat pump system of claim 11 wherein the power generating expander is designed to provides all of the generated power in the form of mechanical shaft power and further designed for the mechanical shaft power to power the mass flow regulator.
 15. The heat pump system of claim 14 further comprised of a back pressure regulator for the heat pump thermodynamic loop wherein the back pressure regulator is designed to vary the high-side pressure of the heat pump thermodynamic loop to consume all of the mechanical shaft power generated by the power generating expander.
 16. The heat pump system of claim 11 further comprised of an electric motor wherein the electric motor is designed to generate mechanical shaft power to operate the one mass flow regulator.
 17. The heat pump system of claim 16 further comprised of an electric motor decoupler designed to either electrically or magnetically decouple the electric motor or mechanically disconnect the electric motor from both the one mass flow regulator and the power generating expander.
 18. The heat pump system of claim 16 further comprised of an electric motor coupled designed to either electrically or magnetically engage the electric motor or mechanically connected the electric motor to the one mass flow regulator.
 19. The heat pump system of claim 1 further comprised of a fluid accumulator tank in fluid communication with both high-side pressure circuit and low-side pressure circuit, wherein the one mass flow regulator is designed to switch between a mode to remove working fluid from the high-side pressure circuit into the fluid accumulator and a mode to add working fluid from the fluid accumulator into the low-side pressure circuit, and wherein the fluid communication with the fluid accumulator is designed to be void of a second mass flow regulator consuming greater than 20 watts of mechanical or electrical power.
 20. The heat pump system of claim 19 further comprised of a heat exchanger in thermal communication with the fluid accumulator tank, and wherein the working fluid is operable at a working fluid pressure having a decrease in density per 10 degrees Fahrenheit increase of at least one percent.
 21. The heat pump system of claim 20 wherein the fluid accumulator is further comprised of at least one fluid inlet port and at least one fluid discharge port.
 22. The heat pump system of claim 21 wherein the at least one fluid inlet port into the fluid accumulator is in fluid communication with the high-side pressure circuit and the at least one fluid discharge port from the fluid accumulator is in fluid communication with the low-side pressure circuit.
 23. The heat pump system of claim 22 wherein the at least one fluid inlet port is at least one inch higher than the at least one fluid discharge port.
 24. The heat pump system of claim 22 wherein the method of adding working fluid into the at least one thermodynamic cycle is designed to have volumetric displacement of working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent lower than the working fluid within the fluid accumulator.
 25. The heat pump system of claim 24 wherein the method of adding working fluid into the at least one thermodynamic cycle has an increased rate of fluid addition of at least 5 percent by preheating the temperature of the high-pressure circuit side by at least 10 degrees Fahrenheit greater than the working fluid temperature within the fluid accumulator.
 26. The heat pump system of claim 24 further comprised of solar collectors downstream of the one mass flow regulator consuming at least 20 watts of power operable to increase the working fluid temperature by at least 5 degrees Fahrenheit for adding working fluid into the at least one thermodynamic cycle.
 27. The heat pump system of claim 24 further comprised of solar collectors downstream of the one mass flow regulator consuming at least 20 watts of power operable to decrease the working fluid temperature by at least 5 degrees Fahrenheit for removing working fluid from the at least one thermodynamic cycle into the fluid accumulator, wherein the solar collector is operable in a thermal emitter mode.
 28. The heat pump system of claim 24 further comprised of a thermal source downstream of the one mass flow regulator consuming at least 20 watts of power operable to increase the working fluid temperature by at least 5 degrees Fahrenheit for adding working fluid into the at least one thermodynamic cycle.
 29. The heat pump system of claim 24 further comprised of at least one fluid valve control designed to add a circuit containing working fluid or to decrease the temperature of working fluid within the high-side circuit pressure and having a thermal sink downstream of the one mass flow regulator consuming at least 20 watts of power and operable to add working fluid into the at least one thermodynamic cycle high-side circuit pressure.
 30. The heat pump system of claim 24 wherein the method of adding working fluid into the at least one thermodynamic cycle has an increased rate of fluid addition of at least 5 percent by cooling the working fluid temperature within the fluid accumulator by at least 5 degrees Fahrenheit.
 31. The heat pump system of claim 22 wherein the method of removing working fluid from the at least one thermodynamic cycle is designed to have volumetric displacement of working fluid in the fluid accumulator with working fluid from the high-pressure circuit side having a density of at least one percent greater than the working fluid within the fluid accumulator.
 32. The heat pump system of claim 1 further comprised of two overlapping thermodynamic cycles with a first thermodynamic cycle as a power generating thermodynamic loop having a low-side pressure circuit upstream of a power generating expander and a high-side pressure circuit downstream of a power generating expander and a second thermodynamic cycle having a low-side pressure circuit upstream of the one mass flow regulator and a high-side pressure circuit downstream of the one mass flow regulator, wherein the high-side pressure circuit of the second thermodynamic cycle is at least 5 psi greater than the low-side pressure circuit of the first thermodynamic cycle.
 33. The heat pump system of claim 1 further comprised of a solid state conversion device including photovoltaic, thermophotovoltaic, thermoelectric, or thermionic cell having a maximum junction temperature; and a backpressure regulator designed to modulate the operating pressure downstream of the one mass flow regulator wherein the operating pressure maintains a phase change working fluid temperature within 5 degrees Fahrenheit of the lesser of solid state conversion device maximum junction temperature or design temperature.
 34. The heat pump system of claim 1 further comprising a second thermodynamic cycle having a power generating expander in mechanical communication with the one mass flow regulator circulating the working fluid, and a combustor having combustor exhaust, wherein the at least one thermodynamic cycle is the first thermodynamic cycle and both the first thermodynamic cycle and second thermodynamic cycle have the same working fluid, wherein the heat pump system has a coefficient of performance greater than 1.20, and wherein the combustor is at least one thermal source for the second thermodynamic cycle and the combustor exhaust is at least one thermal source for the first thermodynamic cycle.
 35. The heat pump system of claim 34 further comprising a solar collector having the same working fluid as both the first thermodynamic cycle and the second thermodynamic cycle; further comprising a heat exchanger from a low-pressure circuit side of the first thermodynamic cycle to a low-pressure circuit side of the second thermodynamic cycle and wherein the second thermodynamic cycle is void of any heat exchangers having thermal communication between a high-pressure circuit side of second thermodynamic cycle and low-pressure circuit side of second thermodynamic cycle.
 36. The heat pump system of claim 35 wherein the working fluid is carbon dioxide, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2000 psi, the high-side circuit pressure of the first thermodynamic cycle is greater than 800 psi.
 37. The heat pump system of claim 35 wherein the working fluid is carbon dioxide, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2700 psi, wherein the high-side circuit pressure of the first thermodynamic cycle is greater than 1200 psi, wherein the high-side circuit pressure of the second thermodynamic cycle is greater than 2.2 times the low-side circuit pressure of the second thermodynamic cycle, and wherein the high-side circuit pressure of the first thermodynamic cycle is at least 5 psi greater than the low-side circuit pressure of the second thermodynamic cycle.
 38. The heat pump system of claim 35 further comprised of a heat exchanger to transfer thermal energy from the second thermodynamic cycle low-pressure circuit side to a regenerator of a dehumidification system operable to provide latent cooling, and a heat exchanger from the first thermodynamic cycle high-pressure circuit side operable as a condenser and wherein the first thermodynamic cycle is operable in a cooling mode and the second thermodynamic cycle is operable as a mechanically interconnected power source to the at least one mass flow regulator. 